JP2011064249A - Vibration reducing device of engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To save a space by mounting rotors requiring a large space to balance weights and containing them in the inside of a housing, and as a rotation permissible space exists in the housing for permitting rotating motion of the balance weights, by effectively using the rotation permissible space as a space for permitting rotating motion of the rotors. <P>SOLUTION: The vibration reducing device 1 of an engine 3 includes: balancer shafts 20A, 20B including shaft bodies 21A, 21B and the balance weights 23A, 23B and rotating in conjunction with driving of the engine 3 to reduce vibration of the engine 3; the housing 10 containing at least the balance weights 23A, 23B of the balancer shafts 20A, 20B and rotatably supporting the shaft bodies 21A, 21B; and generators 2A, 2B generating electric power by using rotating force of the balancer shafts 20A, 20B. The generators 2A, 2B include the rotors 30A, 30B mounted to the balance weights 23A, 23B to be rotatable with the balance weights and stators 31A, 31B mounted to the housing 10. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an engine vibration reducing device.

  Patent Document 1 discloses a technique for providing a generator in an engine vibration reduction device. This vibration reduction device is configured by housing a balancer shaft in a housing, a rotor is attached to an end portion of the balancer shaft that protrudes outside the housing, and a stator is provided outside the housing. The generator is composed of a rotor and a stator, and generates power using the rotational motion of the balancer shaft.

JP 2000-248958 A

  In the above vibration reducing device, since the generator is arranged outside the housing, a space for arranging the generator outside the housing must be secured. In particular, the rotor requires a large space because it rotates.

  The present invention has been completed based on the above situation, and aims to save space.

  As a means for achieving the above object, the invention of claim 1 comprises a shaft body and a balance weight, and a balancer shaft that reduces vibrations of the engine by rotating in conjunction with driving of the engine, A vibration reduction device for an engine comprising: a housing that accommodates at least the balance weight of the balancer shaft, and that rotatably supports the shaft body; and a generator that generates electric power using the rotational force of the balancer shaft. The generator is characterized in that it comprises a rotor attached to the balance weight so as to rotate integrally with the balance weight, and a stator attached to the housing.

  The invention of claim 2 is characterized in that, in the invention of claim 1, the rotor is embedded in the balance weight.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the engine is disposed above the housing, and the balancer shaft supports the shaft body in a posture in which the shaft main body is oriented substantially horizontally. And the stator is disposed on the lower surface of the housing.

  The invention of claim 4 is characterized in that, in any one of claims 1 to 3, the stator is disposed on an outer surface of the housing.

<Invention of Claim 1>
A rotor requiring a large space was accommodated inside the housing by being attached to a balance weight. There is a rotation allowance space in the housing that allows the balance weight to rotate. However, this rotation allowance space must be used effectively as a space to enable the rotor to rotate. Can do. Thereby, space saving can be achieved.

<Invention of Claim 2>
When the rotor is arranged on the outer surface of an existing balance weight in which the rotor is not embedded, there is a concern that the center of gravity position of the balance weight is greatly deviated from the center of gravity of the balance weight before the rotor is attached. In that respect, in the present invention, since the rotor is embedded in the balance weight, the position of the center of gravity does not have to be greatly deviated from the position of the center of gravity of the existing balance weight, and the vibration reduction function caused by the shift of the center of gravity is reduced. Can be avoided.

<Invention of Claim 3>
Since the stator is disposed at the lower surface of the housing, that is, at a position opposite to the housing across the housing, it is not necessary to change the positional relationship between the housing and the engine and the shape of the upper surface side of the housing.

<Invention of Claim 4>
When the stator is disposed inside the housing, there is a concern that an existing housing cannot be diverted because a space for accommodating the stator must be secured inside the housing. In that respect, in the present invention, since the stator is disposed on the outer surface of the housing, the existing housing can be used.

Sectional drawing showing arrangement | positioning of the rotor and stator which comprise a generator in Embodiment 1. FIG. Top view showing the housing with the upper case removed

<Embodiment 1>
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. The vibration reduction device 1 of the present embodiment is configured by housing a first balancer shaft 20A and a second balancer shaft 20B in a housing 10 made of a nonmagnetic material, and also includes a first generator 2A and a second generator. 2B. An engine 3 is disposed in the vicinity above the vibration reducing device 1. The engine 3 is provided with a crankshaft (not shown), and the lower end portion of the crankshaft of the crankshaft protrudes toward the lower surface side of the engine 3.

  The housing 10 is configured by vertically stacking a lower case 11 and an upper case 12, and the housing 10 has a space for rotatably accommodating the first balancer shaft 20A and the second balancer shaft 20B. One rotation permissible space 13, two first bearing holes 14A, and two second bearing holes 14B are formed. The rotation allowable space 13 accommodates the balance weights 23A and 23B of the two balancer shafts 20A and 20B, and functions as a space for allowing the rotation of the two balance weights 23A and 23B.

  Each of the bearing holes 14A and 14B has a through-hole shape with a circular cross section for rotatably supporting the shaft portions 25A and 25B of the balancer shafts 20A and 20B. The two first bearing holes 14 </ b> A are for supporting the shaft portion 25 </ b> A of the first balancer shaft 20 </ b> A, and are arranged coaxially with each other with the rotation allowable space 13 interposed therebetween. The two second bearing holes 14B are for rotatably supporting the shaft portion 25B of the second balancer shaft 20B. Like the first bearing holes 14A, the two second bearing holes 14B are arranged coaxially with the rotation allowable space 13 therebetween. Has been. Further, the first bearing hole 14A and the second bearing hole 14B are disposed at substantially the same height.

  Further, the lower case 11 is formed with a gear housing space 15 having a shape in which the upper surface is cut out. The gear housing space 15 is a space for housing the driven gear 22 of the first balancer shaft 20A, and is opposite to the rotation-allowable space 13 with one of the two first bearing holes 14A sandwiching the first bearing hole 14A. Arranged on the side.

  The first balancer shaft 20A is configured such that the first shaft main body 21A, the driven gear 22, the first balance weight 23A, and the first interlocking gear 24A can rotate integrally. The driven gear 22 is disposed at a position close to one end of the first shaft main body 21A. Since the first balance weight 23A has a substantially semicircular shape coaxial with the first shaft body 21A when viewed in parallel with the axis of the first shaft body 21A, the center of gravity of the first balance weight 23A itself is It is in a position eccentric from the axis of 21A. The first balance weight 23A is made of a nonmagnetic material and has a predetermined thickness in the axial direction of the first shaft body 21A.

  24 A of 1st interlocking gears are arrange | positioned so that it may overlap with the end surface of the side facing the driven gear 22 among the both end surfaces in the axial direction of 1st balance weight 23A. The end portion of the first shaft body 21A opposite to the driven gear 22 and the portion between the driven gear 22 and the first interlocking gear 24A are all the first shaft portion 25A. A pair of first flange portions 26A is formed at both ends of the first shaft portion 25A located between the driven gear 22 and the first interlocking gear 24A of the two first shaft portions 25A.

  The first balancer shaft 20A is configured such that the two first shaft portions 25A are rotatably fitted in the two first bearing holes 14A, so that the axis of the first shaft body 21A is oriented in the horizontal direction. Is supported rotatably. Further, the first balancer shaft 20 </ b> A is restricted from moving relative to the housing 10 in the axial direction by sliding the pair of first flange portions 26 </ b> A against the hole edges of the first bearing holes 14 </ b> A.

  With the first balancer shaft 20 </ b> A attached to the housing 10, the lower half area of the driven gear 22 is accommodated in the gear accommodating space 15, and the upper half area of the driven gear 22 is exposed to the outside of the housing 10. The exposed portion of the driven gear 22 is engaged with the crank gear of the engine 3, and the rotational force of the crankshaft is transmitted to the first balancer shaft 20 </ b> A via the driven gear 22. The first balance weight 23 </ b> A and the first interlocking gear 24 </ b> A are accommodated in the rotation allowable space 13. The first balance weight 23A and the first interlocking gear 24A occupy a substantially ½ region in the rotation permissible space 13 in the horizontal direction perpendicular to the axis lines of both balancer shafts.

  The second balancer shaft 20B is configured such that the second shaft main body 21B, the second balance weight 23B, and the second interlocking gear 24B can rotate integrally. The second balance weight 23B is disposed at a substantially central position in the axial direction of the second shaft main body 21B. Since the second balance weight 23B has a substantially semicircular shape coaxial with the second shaft body 21B when viewed in parallel with the axis of the second shaft body 21B, the center of gravity of the second balance weight 23B itself is the second shaft body. It is in a position eccentric from the axis of 21B. The second balance weight 23B is made of a nonmagnetic material and has a predetermined thickness in the axial direction of the second shaft body 21B.

  The second interlocking gear 24B is disposed so as to overlap the end surface of one of the both end surfaces in the axial direction of the first balance weight 23A (the driven gear 22 side when both balancer shafts 20A and 20B are attached to the housing 10). Yes. Both end portions of the second shaft main body 21B in the axial direction are second shaft portions 25B, and the two second shaft portions 25B sandwich the second balance weight 23B and the second interlocking gear 24B. Is located. A pair of second flange portions 26B are formed at both ends of the second shaft portion 25B on the driven gear 22 side in a state of being attached to the housing 10 among the two second shaft portions 25B.

  The second balancer shaft 20B has two second shaft portions 25B rotatably fitted in the two second bearing holes 14B, so that the axis of the second shaft main body 21B is horizontal and the first shaft main body 21A and It is rotatably supported with respect to the housing 10 in a parallel orientation. Further, the second balancer shaft 20 </ b> B is restricted from moving relative to the housing 10 in the axial direction by sliding the pair of second flange portions 26 </ b> B against the hole edges of the second bearing holes 14 </ b> B.

  When the second balancer shaft 20B is attached to the housing 10, the second balance weight 23B and the second interlocking gear 24B are accommodated in the rotation allowable space 13. The second balance weight 23B and the second interlocking gear 24B occupy a substantially ½ region in the rotation allowable space 13 in the horizontal direction perpendicular to the axes of the balancer shafts 20A and 20B. Further, in the rotation permissible space 13, the first interlocking gear 24A and the second interlocking gear 24B are engaged, and the rotational force transmitted from the crankshaft to the first balancer shaft 20A via the driven gear 22 is the both interlocking gears 24A. , 24B is transmitted to the second balancer shaft 20B. As a result, the first balancer shaft 20A and the second balancer shaft 20B rotate in opposite directions to each other in a state where they are aligned horizontally with their axes parallel.

  Further, when the first balancer shaft 20A and the second balancer shaft 20B rotate in the opposite directions in conjunction with each other, the first balance weight 23A and the second balance weight 23B are parallel to the axes of the balancer shafts 20A and 20B. It is designed to rotate eccentrically while maintaining a symmetric positional relationship with respect to a virtual axis (not shown). As described above, the two balance weights 23 </ b> A and 23 </ b> B rotate eccentrically in conjunction with the driving of the engine 3, so that the vibration of the engine 3 is reduced.

  Next, the first generator 2A and the second generator 2B will be described with reference to FIG. The first generator 2A includes a plurality of first rotors 30A and a plurality of first stators 31A. Each of the plurality of first rotors 30A is made of a permanent magnet, and is provided on the first balance weight 23A. When viewed in the axial direction of the first balancer shaft 20A, the plurality of first rotors 30A are arranged at a constant pitch along a circumference concentric with the first balancer shaft 20A. Each first rotor 30A is provided in a state where the entire first rotor 30A is embedded in the first balance weight 23A. The plurality of first rotors 30A are integrally moved with the first balance weight 23A so as to rotate on a certain circumference.

  Each of the plurality of first stators 31A is made of a coil, and is fixed to the outer surface (lower surface) of the first lower surface wall 16A having an arc shape concentric with the first balancer shaft 20A in the lower case 11 constituting the housing 10. Is provided. The fixed position of the first stator 31 </ b> A is outside the housing 10, and is upside down with respect to the engine 3 with the housing 10 interposed therebetween. Further, when viewed in the axial direction of the first balancer shaft 20A, the plurality of first stators 31A are arranged at a constant pitch along a circumference concentric with the first balancer shaft 20A.

  The second generator 2B includes a plurality of second rotors 30B and a plurality of second stators 31B. Each of the plurality of second rotors 30B is made of a permanent magnet, and is provided on the second balance weight 23B. When viewed in the axial direction of the second balancer shaft 20B, the plurality of second rotors 30B are arranged at a constant pitch along a circumference concentric with the second balancer shaft 20B. Each of the second rotors 30B is provided in a state where the entire second rotor 30B is embedded in the second balance weight 23B. The plurality of second rotors 30B are integrally rotated with the second balance weight 23B so as to rotate on a certain circumference.

  Each of the plurality of second stators 31B is formed of a coil, and is fixed to the outer surface (lower surface) of the second lower surface wall 16B having an arc shape concentric with the second balancer shaft 20B in the lower case 11 constituting the housing 10. Is provided. The fixed position of the second stator 31B is outside the housing 10 and is a position upside down from the engine 3 with the housing 10 in between. Further, when viewed in the axial direction of the second balancer shaft 20B, the plurality of second stators 31B are arranged at a constant pitch along a circumference concentric with the second balancer shaft 20B.

  In the generators 2A and 2B according to the present embodiment, the rotors 30A and 30B are rotated integrally with the balancer shafts 20A and 20B, and the rotors 30A and 30B generate the balance weights 23A and 23B. Since it is attached so that it can rotate integrally, it is accommodated in the inside of the housing 10. Inside the housing 10, there is a rotation-allowable space 13 as a space for allowing the balance weights 23A, 23B to rotate. The rotation-allowable space 13 is used to rotate the rotors 30A, 30B. It is also effectively used as a space to make it possible. Therefore, space can be saved in this embodiment compared with the case where the rotor is arranged outside the housing.

  In addition, when the rotor is arranged on the outer surface of an existing balance weight in which the rotor is not embedded, there is a concern that the center of gravity position of the balance weight may deviate greatly from the position of the balance weight before the rotor is attached. The In this respect, in the present embodiment, the rotors 30A and 30B are embedded in the balance weights 23A and 23B, so that there is no possibility that the position of the center of gravity greatly deviates from the position of the center of gravity of the existing balance weight. It is possible to avoid the deterioration of the vibration reduction function.

  Further, in the present embodiment, focusing on the form in which the engine 3 is positioned above the housing 10 and the balancer shafts 20A and 20B are supported with the shaft main bodies 21A and 21B oriented substantially horizontally, the stator 31A , 31B are arranged on the lower surface of the housing 10. As described above, the stators 31A and 31B are arranged on the lower surface of the housing 10, that is, on the opposite side of the engine 3 with respect to the engine 10, so No need to change the shape.

  Further, when the stator is arranged inside the housing, there is a concern that the existing housing cannot be used because a space for accommodating the stator must be secured inside the housing. In that respect, in the present embodiment, since the stators 31A and 31B are arranged on the outer surface of the housing 10, the existing housing 10 can be used.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In the above embodiment, the entire rotor is embedded in the balance weight. However, the rotor may be configured such that only a part of the rotor is embedded in the balance weight and the other part protrudes from the outer surface of the balance weight. Alternatively, the entire rotor may be protruded from the outer surface of the balance weight.
(2) In the above embodiment, the stator is disposed on the lower surface of the housing, that is, on the opposite side of the engine with respect to the housing. However, the stator is disposed on the upper surface of the housing, that is, on the same side as the engine. It may be arranged on the side of the housing.
(3) In the above embodiment, the stator is disposed outside (outer surface) of the housing, but the stator may be disposed inside (inner surface) of the housing.

DESCRIPTION OF SYMBOLS 1 ... Vibration reduction apparatus 2A ... 1st generator 2B ... 2nd generator 3 ... Engine 10 ... Housing 20A ... 1st balancer shaft 20B ... 2nd balancer shaft 21A ... 1st shaft main body 21B ... 2nd shaft main body 23A ... 2nd 1 balance weight 23B ... 2nd balance weight 30A ... 1st rotor 30B ... 2nd rotor 31A ... 1st stator 31B ... 2nd stator

Claims (4)

A balancer shaft configured to include a shaft body and a balance weight, and to reduce engine vibration by rotating in conjunction with engine driving;
A housing that accommodates at least the balance weight of the balancer shaft and rotatably supports the shaft body;
In the engine vibration reduction device comprising a generator that generates electric power using the rotational force of the balancer shaft,
The generator is
A rotor attached to be able to rotate integrally with the balance weight;
An engine vibration reduction device comprising a stator attached to the housing.   The engine vibration reducing device according to claim 1, wherein the rotor is embedded in the balance weight. The engine is disposed above the housing;
The balancer shaft is supported in a posture in which the shaft main body is oriented substantially horizontally;
The engine vibration reducing device according to claim 1, wherein the stator is disposed on a lower surface of the housing.   The engine vibration reducing device according to any one of claims 1 to 3, wherein the stator is disposed on an outer surface of the housing.

Images